On vehicles traveling using electricity as motive power, storage batteries including lead batteries, nickel-hydride batteries, and lithium-ion batteries are mounted. The electric power necessary when hybrid cars and electric cars travel is provided by these storage batteries.
The following PTL 1 has disclosed, as a method of properly setting an input limit and an output limit of a battery, a technology of setting a limit value by comparing a time-average value of square values of charge and discharge currents with a threshold value.
The following PTL 2 has disclosed that an allowable current allowing charge and discharge of a battery is specified by an average current of absolute values of charge and discharge currents. Further, the PTL 2 has disclosed that the allowable current is made smaller as a time for detection of the average current is longer.